Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States; Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, United States.
Department of Orthopaedics, University of Utah, Salt Lake City, UT, United States.
J Biomech. 2021 Mar 5;117:110266. doi: 10.1016/j.jbiomech.2021.110266. Epub 2021 Jan 23.
Age affects gross shoulder range of motion (ROM), but biomechanical changes over a lifetime are typically only characterized for the humerothoracic joint. Suitable age-related baselines for the scapulothoracic and glenohumeral contributions to humerothoracic motion are needed to advance understanding of shoulder injuries and pathology. Notably, biomechanical comparisons between younger or older populations may obscure detected differences in underlying shoulder motion. Herein, biplane fluoroscopy and skin-marker motion analysis quantified humerothoracic, scapulothoracic, and glenohumeral motion during 3 static poses (resting neutral, internal rotation to L4-L5, and internal rotation to maximum reach) and 2 dynamic activities (scapular plane abduction and external rotation in adduction). Orientations during static poses and rotations during active ROM were compared between subjects <35 years and >45 years of age (N = 10 subjects per group). Numerous age-related kinematic differences were measured, ranging 5-22°, where variations in scapular orientation and motion were consistently observed. These disparities are on par with or exceed mean clinically important differences and standard error of measurement of clinical ROM, which indicates that high resolution techniques and appropriately matched controls are required to avoid confounding results of studies that investigate shoulder kinematics. Understanding these dissimilarities will help clinicians manage expectations and treatment protocols where indications and prevalence between age groups tend to differ. Where possible, it is advised to select age-matched control cohorts when studying the kinematics of shoulder injury, pathology, or surgical/physical therapy interventions to ensure clinically important differences are not overlooked.
年龄会影响肩部总活动度（ROM），但一生中的生物力学变化通常仅针对肩胸关节进行描述。需要确定与年龄相关的肩胛胸壁和盂肱关节对肩胸运动的基础线，以深入了解肩部损伤和病理。值得注意的是，在年轻或年老人群之间进行生物力学比较可能会掩盖对潜在肩部运动差异的检测。本研究采用双平面荧光透视和皮肤标记运动分析技术，在 3 个静态姿势（休息中立位、内旋至 L4-L5 和内旋至最大活动范围）和 2 个动态活动（肩胛平面外展和内收时的外旋）下定量测量肩胸关节、肩胛胸壁关节和盂肱关节的运动。比较了<35 岁和>45 岁的受试者在静态姿势下的体位和主动活动范围旋转时的体位（每组 10 名受试者）。测量了许多与年龄相关的运动学差异，范围为 5-22°，其中肩胛的位置和运动的变化一直存在。这些差异与临床 ROM 的平均重要差异和测量标准误差相当，甚至超过了这些数值，这表明需要使用高分辨率技术和适当匹配的对照来避免研究肩部运动学的混淆结果。了解这些差异将有助于临床医生在处理不同年龄段之间的适应症和患病率存在差异的肩部损伤、病理或手术/物理治疗干预的期望和治疗方案。在研究肩部损伤、病理或手术/物理治疗干预的运动学时，如果可能，建议选择年龄匹配的对照组，以确保不会忽略具有临床意义的差异。
